Efficacy of Treatments Compared for Female Pattern Hair Loss

The safety and efficacy of topical minoxidil for the treatment of female pattern hair loss was supported by moderate to low quality evidence in a recent Cochrane systematic review.

Female pattern hair loss, or androgenic alopecia, is the most common form found in women. Esther J van Zuuren, from Leiden University Medical center, Ledien, Netherlands, and colleagues conducted a review to determine the safety and efficacy of available options for the treatment of female pattern hair loss. They searched various databases and trial registries as well as the reference lists of included and excluded studies to include randomized-controlled trials evaluating the efficacy of interventions for female pattern hair loss in women.

A total of 47 studies including 5,290 study patients, were included for the analysis; 17 of the studies evaluated minoxidil. Pooled data from 6 studies showed that more patients treated with minoxidil 2% (one study with 1%) showed a moderate to marked increase in hair regrowth vs. placebo (risk ratio [RR] 1.93, 95% CI: 1.51–2.47; moderate quality evidence). Separate investigator-rated assessments in 7 studies including 1,191 patients further supported these results (RR 2.35, 95% CI: 1.68–3.28; moderate quality evidence). One study involving 260 study patients reported on quality of life though it was inadequate with low quality evidence.

In eight studies (n=1, 242), a significant increase of 13.18 in total hair count/cm2 was seen in the minoxidil group vs. the placebo group (95% CI: 10.92–15.44; low quality evidence). Regarding adverse events, there were 40/407 events in the minoxidil 2% group vs. 28/320 events in the placebo group (RR 1.24, 95% CI: 0.82–1.87; low quality evidence).

When compared to minoxidil 5%, data from one study showed patients in the minoxidil 2% group had moderate to greatly increased hair regrowth (RR 1.12, 95% CI: 0.72–1.73). Another study showed no difference based on a visual analogue scale (P=0.062; low quality evidence). Both strengths of minoxidil did not demonstrate a difference in increase in total hair count at the end of the study in three trials involving 631 study patients (mean difference [MD] –2.12, 95% CI: –5.47 to 1.23; low quality evidence).

Study authors found inconsistent results in the trials that assessed laser devices (moderate to low quality evidence) but did see an improvement in total hair count measured from baseline. They added that more randomized-controlled trials of other commonly used treatments (eg, spironolactone, different finasteride doses, dutasteride, cyproterone acetate, and laser-based therapy) are necessary.